Dear all,
last night I did some first test on 500kHz after my "summer recess".
Good:
I found out that my digging over the past months had some success,
the antenna current is up with 10% (now 2.2A).
Based on antenna simulation (with MMANA-GAL) the theoretical EIRP
should be 4.7 Watt, close to my 5 W EIRP limit. But I guess that in
reality it will be some dB less due to absorption in the surrounding
greenery. I will have to do some ERP measurements to check how much is lost.
At 20.30 UT I could see my signal on various grabbers, up to the Shetlands.
Bad:
I found out that some bad "machine gun type" interference has shown
up. The noise blanker of the TS440 can bring it down a bit, but it
still compromises any weak signal reception. I can null it out with a
loop, but unfortunately it is the same direction as southern UK. So
using a loop RX antenna is not a good solution.
If I cannot track down (and shut down) the source of interference I
will have to cancel it out some way.
An additional noise blanker?
Or picking up the interference signal with a local "sense antenna"
and use that to phase it out (combine it with the right phase and
amplitude with the signal from the main antenna)?
All suggestions are welcome.
73, Rik ON7YD
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